Free Online Metronome

How to use the metronome

1. Set the tempo: type it into the big number, drag the fader, or press the minus and plus keys. Anything from 20 to 300 BPM works.
2. Choose a time signature. The row of lamps shows one lamp per beat of the bar.
3. Press Start or the Space bar. The number of the beat you are hearing lights up under its lamp. Press again to stop.
4. Change anything while it plays: the tempo, the signature, the clicks per beat or a beat's lamp. The change lands on the next click.

To match a song, press T or the Tap tempo key on each beat. The tempo follows your taps, averaged over up to the last eight gaps, the same way as the BPM tapper.

Time signatures and accents

The top number of a time signature is how many beats are in a bar; the bottom number is the note that gets one beat (4 is a quarter note, 8 an eighth). The metronome clicks once per beat and starts each bar on beat 1.

• 2/4, 3/4 and 4/4 accent beat 1 only. 4/4 is the meter of most pop, rock, hip-hop and dance music; 3/4 is the waltz.
• 5/4 accents beat 1. Many 5/4 pieces feel like 3+2 or 2+3: click the lamp on beat 4 or beat 3 to accent the second group.
• 6/8 and 12/8 click every eighth note and accent each group of three, so you hear two (6/8) or four (12/8) strong pulses per bar. Set the tempo in eighth notes.
• 7/8 starts as 2+2+3, with accents on 1, 3 and 5. For 3+2+2, click the lamps to accent 1, 4 and 6 instead.

Every lamp steps through three states when you click it: accent (lit, a higher click), click (half lit) and silent (dark). The first beat of the bar, when accented, gets the highest click of all, so the top of the bar is always clear. Choosing a time signature again resets its lamps.

Subdivisions: eighths, triplets and sixteenths

Clicks per beat splits every beat into equal, quieter clicks between the main ones. 8ths adds one click per beat, Triplets two and 16ths three. Hearing the subdivision makes it easier to place notes that fall between the beats, and to keep a slow tempo from dragging, because the gaps between clicks are shorter.

A silent beat silences its subdivisions too, so a muted beat leaves a full gap for you to fill.

Tempo markings

Classical scores often name a tempo in Italian instead of giving a number. The ranges below are the approximate ones listed on Wikipedia's Tempo article. They are rough and they overlap: the right tempo for a marking varies by composer and by piece, so treat these as starting points.

For the usual tempo of a style rather than a marking, see BPM by genre.

How it keeps time

A web page's timers can run late whenever the browser is busy, so a metronome that played a click each time a timer fired would wobble. This one books its clicks on the Web Audio clock instead, the clock that drives the sound itself: every 25 ms it schedules any click due in the next 100 ms at its exact time. A busy page can delay the booking, but not the clicks. This is the method described in A tale of two clocks on web.dev.

Each click is a short tone generated in the browser: no samples are downloaded, and nothing you do is recorded or sent.

Practicing with a click

• Start slower than you think. Pick a tempo where you can play the passage cleanly every time, then raise it a few BPM at a time.
• Use subdivisions at slow tempos. The slower the tempo, the longer the gap between beats and the easier it is to drift inside it. Eighths or triplets fill the gap.
• Click on 2 and 4. For swing and backbeat styles, set beats 1 and 3 to silent so the click lands only on 2 and 4, where the snare would.
• Test your own time. Mute one or two beats of the bar and see whether you are still with the click when it comes back.

Recording to a click in a DAW? Set the session to the same tempo, and use the delay calculator to turn it into delay times in milliseconds.

<a href="https://vitricaudio.com/tools/metronome">Online metronome</a> by Vitric Audio